Many wireless communication systems and other radio-frequency applications use power amplifiers for increasing the power of a signal. These systems often require use of high power transistors and other high power components that need a heat dissipation structure. Traditionally, the high power components are provided as a separately packaged device which is soldered to a printed circuit board that has a copper heat transfer component.
An issue with the traditional method of incorporating high power components as a packaged device is that this results in a large size of systems having those components. Each component is added as a separate package; for example, some high power transistors are provided in a gull-winged configuration package that is mounted on a printed circuit board (PCB). These configurations can have imperfect transfer of heat to heat sinks incorporated in the PCBs because of poor connections in the large packages. Further, the large component packages can have high parasitic properties, matching circuitry cannot be brought close to the high power device die, and there are significant limitations on device die orientation due to package configuration. All of these features can affect performance, size, and cost of systems incorporating the high power components.
There is also a drive to have smaller system packages, for example, in order to optimize space utilization and to decrease costs associated with large power packages. It is desirable to incorporate thermal device management in these smaller packages along with a more flexible coupling to the package interconnect.
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